Nitrogen-filling welding method for copper tube and nitrogen-filling welding control device

Abstract

The invention relates to a copper tube nitrogen charging and welding method and a nitrogen charging and welding control device. The welding method includes the following steps: a first step of parameter setting, a second step of welding, and a third step of last welding. In the parameter setting step, the pressure value of nitrogen charging is set no more than 0.05MPa, and a flow value of nitrogen charging is correspondingly set according to the cross section area of a copper tube. In the welding step, nitrogen is charged in the copper tube for welding according to parameters set in the first step. In the last welding step, flow of the nitrogen is reduced to no less than 1L / min. The invention further relates to the welding control device using the welding method. The welding control device comprises a nitrogen bottle, a pressure reducing valve, a pressure meter, a nitrogen pipe and a gas flow meter. In a practice base or a laboratory, according to the technical scheme, the oxidation phenomenon caused during welding of the copper tube is effectively prevented. The method and device can be popularized and applied to the industrial fields such as welding of air conditioner cooling pipelines, prevents an oxidation layer from being formed in a tube, reduces the fault rate of a cooling system, and improves quality of air conditioning products.

Description

technical field [0001] The invention relates to a method and device for nitrogen-filled welding of copper pipes, in particular to a method popularized and applied to nitrogen-filled welding of air-conditioning copper pipes and a nitrogen-filled welding control device using the nitrogen-filled welding method. Background technique [0002] In the practice base of quality education for middle school students, there are six standard training workshops including machinery, mould, numerical control, electromechanical, welding, and auto repair. The practical operation items mainly include fitter processing, electronic control circuit production, simple robot production, and numerical control processing. , car maintenance, pipeline welding, etc. Middle school students choose one of the practical projects according to their own interests according to the difficulty and time required for the practical projects, and complete them independently or in groups. Each training workshop is e...

AI Technical Summary

Problems solved by technology

A large number of oxide films produced lead to fatal failures in the air conditioning system, oxides lead to capillary or expansion valve blockage, abnormal exhaust temperature, compressor cylinder stuck, air conditioning system does not cool or heat quality problems

After a lot of investigation and analysis, foreign matter blocking the oil return hole of the gas-liquid separator is the main cause of the compressor cylinder

[0004] At present, when nitrogen is injected into the traditional air-conditioning copper tube welding, only the nitrogen filling pressure is controlled, but the flow of nitrogen gas has not been scientifically calculated and optimized. In this way, it can not only ensure that no oxides are produced during welding of copper pipes, but also ensure the reasonable use of nitrogen.

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